The long term objectives of this work are to gain an understanding of the regulation of eucaryotic cell proliferation. In particular, we hope to examine the coordination of synthesis and modification of proteins in response to stress and also during the cell division cycle of Saccharomyces cerevisiae. The goals for the current year have been: 1) to evaluate the relationship between P17 and P17, two phosphorylated proteins, whose levels change upon alpha-factor mediated cell cycle arrest; 2) to determine if any biological correlates exist for the yeast heat shock response; and 3) identification and purification of the mRNAs coding for the heat shock inducible proteins.